Back to homepage

1.4 Sea-Floor Spreading Notes


Vocabulary

mid-ocean ridge-the longest chain of mountains in the world
sonar-device that bounces sound waves off underwater objects and then records the echoes off these sound waves.
Deep-Ocan trenches-deep underwater canyons
Subduction-the process by which the ocean floor sinks beneath a deep-ocean trench and then back into the mantle.

Outline



Mapping the mid-Ocean ridge

Evidence from sea-floor spreading


  • Evidence from molten material
  • Evidence from magnetic stripes
  • Evidence from Drilling samples

Subduction at Deep-Ocean Trenches

Subduction and Earth's Oceans

  • Subduction in the Pacific Ocean
  • Subduction in the Atlantic Ocean